The present disclosure relates to antennas and, more specifically, to magnetic transmission antennas for ultra-low frequency (ULF) or very low frequency (VLF) radiation.
Some applications require the use of very low frequency (3 to 30 kilo Hertz (kHz)) or ultra-low frequency (0.3 to 3 kHz) radiation. For example, mining operations require through the earth (TTE) communication. A mining operation may involve personnel positioned over 1000 feet underground. When an event (e.g., explosion) requiring emergency aid occurs in the subsurface environment, the personnel must be able to convey information about the event to the surface and must also be able to receive instructions from the surface. In such operations, any radiation above the VLF frequency range is absorbed by the earth.